It has long been recognized that a sterilizaiton of an infant-feeding bottle and nipple, with or without a cap for securing the nipple to the bottle, is advantageous in protecting the infant against pathogenic microorganisms which might be present in the environment or in the milk or formula to be fed to the infant.
The term "sterilization" is used in the sense of inactivation or killing of microorganisms which might be detrimental to the health of the infant.
Naturally, sterilization has been practiced for considerable time on an industrial and medical level and even to various degrees in the home by boiling the bottles and nipples for example.
It is also known to sterilize articles with hot air, with or without circulation, at temperatures of at least 180.degree. C., and to generate somewhat superheated steam at a superatmospheric pressure of, say, 1 atmosphere gauge and a temperature of 120.degree. C. and to contact the articles with the steam.
Modern industrial practice also utilizes electromagnetic energy, for example, ultraviolet radiation, gamma radiation and beta radiation, for the sterilization of articles in large measure. All these techniques, however, are unsuited for household application and hence domestic sterilization has concentrated on simple boiling.
Note should also be taken of the fact that a somewhat more efficient approach is utilized in hospitals and clinics and in stations for the large scale preparation of infant-feeding packages, wherein the bottles and/or nipples can be sterilized in autoclaves with superheated steam or water at elevated temperatures.
Another domestic approach to sterilization is to soak the bottles and nipples for a long period of time in sterilizing solutions, e.g. solutions of chlorine, and thereafter rinse the bottles.
Problems are encountered with most of the methods hitherto used for home sterilization of baby bottles. For example, when a disinfectant agent is utilized, there is always the danger of residual contamination of the bottle or nipple with the disinfectant. Indeed, residues of the disinfectant may accumulate with time on the bottles or the nipples and ultimately may be transferred to the infant, thereby endangering his or her health.
The rinsing of the bottles and nipples in nonsterile water, as is necessary for removal of residues, likewise poses a danger of reintroduction of infectious material.
Boiling likewise can result in residues on the sterile bottles and nipples and frequently is not capable of removing pathogenic microorganisms.